There are two main types of oral contraceptive pill: the combined pill, often called “the pill”, and the progestogen only pill, sometimes called the mini pill. The combined pill contains the hormones oestrogen and progestogen, while the progestogen only pill contains only progestogen. Both are taken daily, are available on prescription, and are very effective when used correctly.
About the progestogen only pill#
Progestogen is similar to a hormone produced by the ovaries. There are two kinds of progestogen only pill:
- Traditional progestogen only pills (the mini pill) contain a very low dose and, to stay effective, must not be taken more than 3 hours late.
- The drospirenone only pill is a newer, low-dose option that remains effective even if a pill is taken up to 24 hours late.
Taken correctly, progestogen only pills are at least 99% effective at preventing pregnancy. With typical use, allowing for missed or late pills, they are about 93% effective.
How it works#
Both progestogen only pills work by thickening the fluid around the cervix (the opening to the uterus), which helps stop sperm from entering. The drospirenone pill also stops the ovaries from releasing an egg, and traditional progestogen only pills can sometimes do this too.
How to use it#
- Take one pill at around the same time every day. The pack contains 28 pills.
- The traditional progestogen only pill has no inactive (sugar) pills. The drospirenone only pill has 4 inactive pills.
- When you start the pill for the first time, or after a break, it can take up to 7 days to start working. Ask your doctor, nurse or pharmacist about the best way to get started.
What can stop it working#
The progestogen only pill might not work if:
- you miss a pill
- you vomit within 3 hours of taking it
- you have very severe diarrhoea
- you are taking certain medications or natural remedies (check with your doctor, nurse or pharmacist)
If you miss a pill#
Traditional progestogen only pill: take the missed pill as soon as you notice (this may mean taking two pills on the same day), continue taking your pills as normal, and use condoms for the next 3 days.
Drospirenone only pill: take the missed pill as soon as you notice (this may mean taking two pills on the same day), continue taking your pills as normal, and use condoms for the next 7 days.
If you have had penis-in-vagina sex without a condom in the 7 days before missing a pill, you may need emergency contraception, or you may need to skip your next inactive pills and start a new pack. What you should do depends on where you are in the pack, so check with your doctor, nurse or pharmacist.
Benefits#
The progestogen only pill:
- starts working quickly
- has a low dose of hormone
- can be used while breastfeeding
- is another choice if you have difficulty taking, or cannot take, oestrogen
Once you stop using it, your fertility quickly returns to normal.
Side effects and safety#
Possible side effects for a small number of users include:
- irregular vaginal bleeding
- headaches
- sore or tender breasts
- changes to your skin
- mood changes
These side effects often settle with time. The progestogen only pill has not been shown to cause weight gain, and there are no known serious health risks from taking it.
The progestogen only pill might not be a good option if you:
- find it difficult to take a tablet at the same time each day
- have been treated for breast cancer
- have severe liver disease
- are taking certain medications that might stop it working (check with your doctor, nurse or pharmacist)
If you become pregnant while taking it#
If you become pregnant while taking the progestogen only pill, the pill will not harm the pregnancy. It is safe to continue the pregnancy (and stop the pill) or to have an abortion.
After having a baby#
You can start the progestogen only pill straight after giving birth, even if you are breastfeeding. You can stop it at any time and your fertility will quickly return.
Where to get it#
Your doctor can provide a prescription that you take to a pharmacy. If you run out of pills and cannot see a doctor for a new prescription, speak to a pharmacist, who can often supply a small quantity. If possible, show them your old pill packet. Many community health services and some public hospitals also have family planning, sexual health or women’s health clinics that provide contraception.
Protection from STIs#
The progestogen only pill does not protect you from sexually transmissible infections (STIs). The best way to reduce the risk of STIs is to use barrier protection, such as external and internal condoms, with all new sexual partners.
Key points#
- The progestogen only pill contains only progestogen and is taken daily, at around the same time each day.
- Taken correctly, it is at least 99% effective; with typical use it is about 93% effective.
- It works mainly by thickening cervical fluid to stop sperm entering; the drospirenone pill also prevents ovulation.
- It can be used while breastfeeding and is an option if you cannot take oestrogen.
- It has no known serious health risks and has not been shown to cause weight gain, but it does not protect against STIs.
Where to get help#
Sources & further reading
For evidence-based global guidance on this topic, consult authoritative public-health bodies such as the World Health Organization (WHO), CDC, NHS, and ECDC.